forked from embassy-rs/embassy
-
Notifications
You must be signed in to change notification settings - Fork 0
/
i2s.rs
1051 lines (881 loc) · 27.4 KB
/
i2s.rs
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
#![macro_use]
//! Support for I2S audio
use core::future::poll_fn;
use core::marker::PhantomData;
use core::mem::size_of;
use core::ops::{Deref, DerefMut};
use core::sync::atomic::{compiler_fence, Ordering};
use core::task::Poll;
use embassy_cortex_m::interrupt::InterruptExt;
use embassy_hal_common::drop::OnDrop;
use embassy_hal_common::{into_ref, PeripheralRef};
use crate::gpio::{AnyPin, Pin as GpioPin};
use crate::interrupt::Interrupt;
use crate::pac::i2s::RegisterBlock;
use crate::util::{slice_in_ram_or, slice_ptr_parts};
use crate::{Peripheral, EASY_DMA_SIZE};
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
#[non_exhaustive]
pub enum Error {
BufferTooLong,
BufferZeroLength,
BufferNotInDataMemory,
BufferMisaligned,
BufferLengthMisaligned,
}
/// I2S configuration.
#[derive(Clone)]
#[non_exhaustive]
pub struct Config {
pub sample_width: SampleWidth,
pub align: Align,
pub format: Format,
pub channels: Channels,
}
impl Config {
pub fn sample_width(mut self, sample_width: SampleWidth) -> Self {
self.sample_width = sample_width;
self
}
pub fn align(mut self, align: Align) -> Self {
self.align = align;
self
}
pub fn format(mut self, format: Format) -> Self {
self.format = format;
self
}
pub fn channels(mut self, channels: Channels) -> Self {
self.channels = channels;
self
}
}
impl Default for Config {
fn default() -> Self {
Self {
sample_width: SampleWidth::_16bit,
align: Align::Left,
format: Format::I2S,
channels: Channels::Stereo,
}
}
}
/// I2S Mode
#[derive(Debug, Eq, PartialEq, Clone, Copy)]
pub struct MasterClock {
freq: MckFreq,
ratio: Ratio,
}
impl MasterClock {
pub fn new(freq: MckFreq, ratio: Ratio) -> Self {
Self { freq, ratio }
}
}
impl MasterClock {
pub fn sample_rate(&self) -> u32 {
self.freq.to_frequency() / self.ratio.to_divisor()
}
}
/// Master clock generator frequency.
#[derive(Debug, Eq, PartialEq, Clone, Copy)]
pub enum MckFreq {
_32MDiv8,
_32MDiv10,
_32MDiv11,
_32MDiv15,
_32MDiv16,
_32MDiv21,
_32MDiv23,
_32MDiv30,
_32MDiv31,
_32MDiv32,
_32MDiv42,
_32MDiv63,
_32MDiv125,
}
impl MckFreq {
const REGISTER_VALUES: &'static [u32] = &[
0x20000000, 0x18000000, 0x16000000, 0x11000000, 0x10000000, 0x0C000000, 0x0B000000, 0x08800000, 0x08400000,
0x08000000, 0x06000000, 0x04100000, 0x020C0000,
];
const FREQUENCIES: &'static [u32] = &[
4000000, 3200000, 2909090, 2133333, 2000000, 1523809, 1391304, 1066666, 1032258, 1000000, 761904, 507936,
256000,
];
/// Return the value that needs to be written to the register.
pub fn to_register_value(&self) -> u32 {
Self::REGISTER_VALUES[usize::from(*self)]
}
/// Return the master clock frequency.
pub fn to_frequency(&self) -> u32 {
Self::FREQUENCIES[usize::from(*self)]
}
}
impl From<MckFreq> for usize {
fn from(variant: MckFreq) -> Self {
variant as _
}
}
/// Master clock frequency ratio
///
/// Sample Rate = LRCK = MCK / Ratio
///
#[derive(Debug, Eq, PartialEq, Clone, Copy)]
pub enum Ratio {
_32x,
_48x,
_64x,
_96x,
_128x,
_192x,
_256x,
_384x,
_512x,
}
impl Ratio {
const RATIOS: &'static [u32] = &[32, 48, 64, 96, 128, 192, 256, 384, 512];
/// Return the value that needs to be written to the register.
pub fn to_register_value(&self) -> u8 {
usize::from(*self) as u8
}
pub fn to_divisor(&self) -> u32 {
Self::RATIOS[usize::from(*self)]
}
}
impl From<Ratio> for usize {
fn from(variant: Ratio) -> Self {
variant as _
}
}
/// Approximate sample rates.
///
/// Those are common sample rates that can not be configured without an small error.
///
/// For custom master clock configuration, please refer to [MasterClock].
#[derive(Clone, Copy)]
pub enum ApproxSampleRate {
_11025,
_16000,
_22050,
_32000,
_44100,
_48000,
}
impl From<ApproxSampleRate> for MasterClock {
fn from(value: ApproxSampleRate) -> Self {
match value {
// error = 86
ApproxSampleRate::_11025 => MasterClock::new(MckFreq::_32MDiv15, Ratio::_192x),
// error = 127
ApproxSampleRate::_16000 => MasterClock::new(MckFreq::_32MDiv21, Ratio::_96x),
// error = 172
ApproxSampleRate::_22050 => MasterClock::new(MckFreq::_32MDiv15, Ratio::_96x),
// error = 254
ApproxSampleRate::_32000 => MasterClock::new(MckFreq::_32MDiv21, Ratio::_48x),
// error = 344
ApproxSampleRate::_44100 => MasterClock::new(MckFreq::_32MDiv15, Ratio::_48x),
// error = 381
ApproxSampleRate::_48000 => MasterClock::new(MckFreq::_32MDiv21, Ratio::_32x),
}
}
}
impl ApproxSampleRate {
pub fn sample_rate(&self) -> u32 {
MasterClock::from(*self).sample_rate()
}
}
/// Exact sample rates.
///
/// Those are non standard sample rates that can be configured without error.
///
/// For custom master clock configuration, please refer to [Mode].
#[derive(Clone, Copy)]
pub enum ExactSampleRate {
_8000,
_10582,
_12500,
_15625,
_15873,
_25000,
_31250,
_50000,
_62500,
_100000,
_125000,
}
impl ExactSampleRate {
pub fn sample_rate(&self) -> u32 {
MasterClock::from(*self).sample_rate()
}
}
impl From<ExactSampleRate> for MasterClock {
fn from(value: ExactSampleRate) -> Self {
match value {
ExactSampleRate::_8000 => MasterClock::new(MckFreq::_32MDiv125, Ratio::_32x),
ExactSampleRate::_10582 => MasterClock::new(MckFreq::_32MDiv63, Ratio::_48x),
ExactSampleRate::_12500 => MasterClock::new(MckFreq::_32MDiv10, Ratio::_256x),
ExactSampleRate::_15625 => MasterClock::new(MckFreq::_32MDiv32, Ratio::_64x),
ExactSampleRate::_15873 => MasterClock::new(MckFreq::_32MDiv63, Ratio::_32x),
ExactSampleRate::_25000 => MasterClock::new(MckFreq::_32MDiv10, Ratio::_128x),
ExactSampleRate::_31250 => MasterClock::new(MckFreq::_32MDiv32, Ratio::_32x),
ExactSampleRate::_50000 => MasterClock::new(MckFreq::_32MDiv10, Ratio::_64x),
ExactSampleRate::_62500 => MasterClock::new(MckFreq::_32MDiv16, Ratio::_32x),
ExactSampleRate::_100000 => MasterClock::new(MckFreq::_32MDiv10, Ratio::_32x),
ExactSampleRate::_125000 => MasterClock::new(MckFreq::_32MDiv8, Ratio::_32x),
}
}
}
/// Sample width.
#[derive(Debug, Eq, PartialEq, Clone, Copy)]
pub enum SampleWidth {
_8bit,
_16bit,
_24bit,
}
impl From<SampleWidth> for u8 {
fn from(variant: SampleWidth) -> Self {
variant as _
}
}
/// Channel used for the most significant sample value in a frame.
#[derive(Debug, Eq, PartialEq, Clone, Copy)]
pub enum Align {
Left,
Right,
}
impl From<Align> for bool {
fn from(variant: Align) -> Self {
match variant {
Align::Left => false,
Align::Right => true,
}
}
}
/// Frame format.
#[derive(Debug, Eq, PartialEq, Clone, Copy)]
pub enum Format {
I2S,
Aligned,
}
impl From<Format> for bool {
fn from(variant: Format) -> Self {
match variant {
Format::I2S => false,
Format::Aligned => true,
}
}
}
/// Channels
#[derive(Debug, Eq, PartialEq, Clone, Copy)]
pub enum Channels {
Stereo,
MonoLeft,
MonoRight,
}
impl From<Channels> for u8 {
fn from(variant: Channels) -> Self {
variant as _
}
}
/// Interface to the I2S peripheral using EasyDMA to offload the transmission and reception workload.
pub struct I2S<'d, T: Instance> {
i2s: PeripheralRef<'d, T>,
irq: PeripheralRef<'d, T::Interrupt>,
mck: Option<PeripheralRef<'d, AnyPin>>,
sck: PeripheralRef<'d, AnyPin>,
lrck: PeripheralRef<'d, AnyPin>,
sdin: Option<PeripheralRef<'d, AnyPin>>,
sdout: Option<PeripheralRef<'d, AnyPin>>,
master_clock: Option<MasterClock>,
config: Config,
}
impl<'d, T: Instance> I2S<'d, T> {
/// Create a new I2S in master mode
pub fn master(
i2s: impl Peripheral<P = T> + 'd,
irq: impl Peripheral<P = T::Interrupt> + 'd,
mck: impl Peripheral<P = impl GpioPin> + 'd,
sck: impl Peripheral<P = impl GpioPin> + 'd,
lrck: impl Peripheral<P = impl GpioPin> + 'd,
master_clock: MasterClock,
config: Config,
) -> Self {
into_ref!(i2s, irq, mck, sck, lrck);
Self {
i2s,
irq,
mck: Some(mck.map_into()),
sck: sck.map_into(),
lrck: lrck.map_into(),
sdin: None,
sdout: None,
master_clock: Some(master_clock),
config,
}
}
/// Create a new I2S in slave mode
pub fn slave(
i2s: impl Peripheral<P = T> + 'd,
irq: impl Peripheral<P = T::Interrupt> + 'd,
sck: impl Peripheral<P = impl GpioPin> + 'd,
lrck: impl Peripheral<P = impl GpioPin> + 'd,
config: Config,
) -> Self {
into_ref!(i2s, irq, sck, lrck);
Self {
i2s,
irq,
mck: None,
sck: sck.map_into(),
lrck: lrck.map_into(),
sdin: None,
sdout: None,
master_clock: None,
config,
}
}
/// I2S output only
pub fn output(mut self, sdout: impl Peripheral<P = impl GpioPin> + 'd) -> OutputStream<'d, T> {
self.sdout = Some(sdout.into_ref().map_into());
OutputStream { _p: self.build() }
}
/// I2S input only
pub fn input(mut self, sdin: impl Peripheral<P = impl GpioPin> + 'd) -> InputStream<'d, T> {
self.sdin = Some(sdin.into_ref().map_into());
InputStream { _p: self.build() }
}
/// I2S full duplex (input and output)
pub fn full_duplex(
mut self,
sdin: impl Peripheral<P = impl GpioPin> + 'd,
sdout: impl Peripheral<P = impl GpioPin> + 'd,
) -> FullDuplexStream<'d, T> {
self.sdout = Some(sdout.into_ref().map_into());
self.sdin = Some(sdin.into_ref().map_into());
FullDuplexStream { _p: self.build() }
}
fn build(self) -> PeripheralRef<'d, T> {
self.apply_config();
self.select_pins();
self.setup_interrupt();
let device = Device::<T>::new();
device.enable();
self.i2s
}
fn apply_config(&self) {
let c = &T::regs().config;
match &self.master_clock {
Some(MasterClock { freq, ratio }) => {
c.mode.write(|w| w.mode().master());
c.mcken.write(|w| w.mcken().enabled());
c.mckfreq
.write(|w| unsafe { w.mckfreq().bits(freq.to_register_value()) });
c.ratio.write(|w| unsafe { w.ratio().bits(ratio.to_register_value()) });
}
None => {
c.mode.write(|w| w.mode().slave());
}
};
c.swidth
.write(|w| unsafe { w.swidth().bits(self.config.sample_width.into()) });
c.align.write(|w| w.align().bit(self.config.align.into()));
c.format.write(|w| w.format().bit(self.config.format.into()));
c.channels
.write(|w| unsafe { w.channels().bits(self.config.channels.into()) });
}
fn select_pins(&self) {
let psel = &T::regs().psel;
if let Some(mck) = &self.mck {
psel.mck.write(|w| {
unsafe { w.bits(mck.psel_bits()) };
w.connect().connected()
});
}
psel.sck.write(|w| {
unsafe { w.bits(self.sck.psel_bits()) };
w.connect().connected()
});
psel.lrck.write(|w| {
unsafe { w.bits(self.lrck.psel_bits()) };
w.connect().connected()
});
if let Some(sdin) = &self.sdin {
psel.sdin.write(|w| {
unsafe { w.bits(sdin.psel_bits()) };
w.connect().connected()
});
}
if let Some(sdout) = &self.sdout {
psel.sdout.write(|w| {
unsafe { w.bits(sdout.psel_bits()) };
w.connect().connected()
});
}
}
fn setup_interrupt(&self) {
self.irq.set_handler(Self::on_interrupt);
self.irq.unpend();
self.irq.enable();
let device = Device::<T>::new();
device.disable_tx_ptr_interrupt();
device.disable_rx_ptr_interrupt();
device.disable_stopped_interrupt();
device.reset_tx_ptr_event();
device.reset_rx_ptr_event();
device.reset_stopped_event();
device.enable_tx_ptr_interrupt();
device.enable_rx_ptr_interrupt();
device.enable_stopped_interrupt();
}
fn on_interrupt(_: *mut ()) {
let device = Device::<T>::new();
let s = T::state();
if device.is_tx_ptr_updated() {
trace!("TX INT");
s.tx_waker.wake();
device.disable_tx_ptr_interrupt();
}
if device.is_rx_ptr_updated() {
trace!("RX INT");
s.rx_waker.wake();
device.disable_rx_ptr_interrupt();
}
if device.is_stopped() {
trace!("STOPPED INT");
s.stop_waker.wake();
device.disable_stopped_interrupt();
}
}
async fn stop() {
compiler_fence(Ordering::SeqCst);
let device = Device::<T>::new();
device.stop();
T::state().started.store(false, Ordering::Relaxed);
poll_fn(|cx| {
T::state().stop_waker.register(cx.waker());
if device.is_stopped() {
trace!("STOP: Ready");
device.reset_stopped_event();
Poll::Ready(())
} else {
trace!("STOP: Pending");
Poll::Pending
}
})
.await;
device.disable();
}
async fn send_from_ram<S>(buffer_ptr: *const [S]) -> Result<(), Error>
where
S: Sample,
{
trace!("SEND: {}", buffer_ptr as *const S as u32);
slice_in_ram_or(buffer_ptr, Error::BufferNotInDataMemory)?;
compiler_fence(Ordering::SeqCst);
let device = Device::<T>::new();
let drop = OnDrop::new(move || {
trace!("TX DROP: Stopping");
let device = Device::<T>::new();
device.disable_tx_ptr_interrupt();
device.reset_tx_ptr_event();
device.disable_tx();
// TX is stopped almost instantly, spinning is fine.
while !device.is_tx_ptr_updated() {}
trace!("TX DROP: Stopped");
});
poll_fn(|cx| {
T::state().tx_waker.register(cx.waker());
if device.is_tx_ptr_updated() {
trace!("TX POLL: Ready");
device.reset_tx_ptr_event();
device.enable_tx_ptr_interrupt();
Poll::Ready(())
} else {
trace!("TX POLL: Pending");
Poll::Pending
}
})
.await;
device.update_tx(buffer_ptr)?;
compiler_fence(Ordering::SeqCst);
drop.defuse();
Ok(())
}
async fn receive_from_ram<S>(buffer_ptr: *mut [S]) -> Result<(), Error>
where
S: Sample,
{
trace!("RECEIVE: {}", buffer_ptr as *const S as u32);
// NOTE: RAM slice check for rx is not necessary, as a mutable
// slice can only be built from data located in RAM.
compiler_fence(Ordering::SeqCst);
let device = Device::<T>::new();
let drop = OnDrop::new(move || {
trace!("RX DROP: Stopping");
let device = Device::<T>::new();
device.disable_rx_ptr_interrupt();
device.reset_rx_ptr_event();
device.disable_rx();
// TX is stopped almost instantly, spinning is fine.
while !device.is_rx_ptr_updated() {}
trace!("RX DROP: Stopped");
});
poll_fn(|cx| {
T::state().rx_waker.register(cx.waker());
if device.is_rx_ptr_updated() {
trace!("RX POLL: Ready");
device.reset_rx_ptr_event();
device.enable_rx_ptr_interrupt();
Poll::Ready(())
} else {
trace!("RX POLL: Pending");
Poll::Pending
}
})
.await;
device.update_rx(buffer_ptr)?;
compiler_fence(Ordering::SeqCst);
drop.defuse();
Ok(())
}
}
/// I2S output
pub struct OutputStream<'d, T: Instance> {
_p: PeripheralRef<'d, T>,
}
impl<'d, T: Instance> OutputStream<'d, T> {
/// Prepare the initial buffer and start the I2S transfer.
pub async fn start<S>(&self, buffer: &[S]) -> Result<(), Error>
where
S: Sample,
{
let device = Device::<T>::new();
let s = T::state();
if s.started.load(Ordering::Relaxed) {
self.stop().await;
}
device.enable();
device.enable_tx();
device.update_tx(buffer as *const [S])?;
s.started.store(true, Ordering::Relaxed);
device.start();
Ok(())
}
/// Stops the I2S transfer and waits until it has stopped.
#[inline(always)]
pub async fn stop(&self) {
I2S::<T>::stop().await
}
/// Sets the given `buffer` for transmission in the DMA.
/// Buffer address must be 4 byte aligned and located in RAM.
/// The buffer must not be written while being used by the DMA,
/// which takes two other `send`s being awaited.
#[allow(unused_mut)]
pub async fn send_from_ram<S>(&mut self, buffer: &[S]) -> Result<(), Error>
where
S: Sample,
{
I2S::<T>::send_from_ram(buffer as *const [S]).await
}
}
/// I2S input
pub struct InputStream<'d, T: Instance> {
_p: PeripheralRef<'d, T>,
}
impl<'d, T: Instance> InputStream<'d, T> {
/// Prepare the initial buffer and start the I2S transfer.
pub async fn start<S>(&self, buffer: &mut [S]) -> Result<(), Error>
where
S: Sample,
{
let device = Device::<T>::new();
let s = T::state();
if s.started.load(Ordering::Relaxed) {
self.stop().await;
}
device.enable();
device.enable_rx();
device.update_rx(buffer as *mut [S])?;
s.started.store(true, Ordering::Relaxed);
device.start();
Ok(())
}
/// Stops the I2S transfer and waits until it has stopped.
#[inline(always)]
pub async fn stop(&self) {
I2S::<T>::stop().await
}
/// Sets the given `buffer` for reception from the DMA.
/// Buffer address must be 4 byte aligned and located in RAM.
/// The buffer must not be read while being used by the DMA,
/// which takes two other `receive`s being awaited.
#[allow(unused_mut)]
pub async fn receive_from_ram<S>(&mut self, buffer: &mut [S]) -> Result<(), Error>
where
S: Sample,
{
I2S::<T>::receive_from_ram(buffer as *mut [S]).await
}
}
/// I2S full duplex stream (input & output)
pub struct FullDuplexStream<'d, T: Instance> {
_p: PeripheralRef<'d, T>,
}
impl<'d, T: Instance> FullDuplexStream<'d, T> {
/// Prepare the initial buffers and start the I2S transfer.
pub async fn start<S>(&self, buffer_out: &[S], buffer_in: &mut [S]) -> Result<(), Error>
where
S: Sample,
{
let device = Device::<T>::new();
let s = T::state();
if s.started.load(Ordering::Relaxed) {
self.stop().await;
}
device.enable();
device.enable_tx();
device.enable_rx();
device.update_tx(buffer_out as *const [S])?;
device.update_rx(buffer_in as *mut [S])?;
s.started.store(true, Ordering::Relaxed);
device.start();
Ok(())
}
/// Stops the I2S transfer and waits until it has stopped.
#[inline(always)]
pub async fn stop(&self) {
I2S::<T>::stop().await
}
/// Sets the given `buffer_out` and `buffer_in` for transmission/reception from the DMA.
/// Buffer address must be 4 byte aligned and located in RAM.
/// The buffers must not be written/read while being used by the DMA,
/// which takes two other `send_and_receive` operations being awaited.
#[allow(unused_mut)]
pub async fn send_and_receive_from_ram<S>(&mut self, buffer_out: &[S], buffer_in: &mut [S]) -> Result<(), Error>
where
S: Sample,
{
I2S::<T>::send_from_ram(buffer_out as *const [S]).await?;
I2S::<T>::receive_from_ram(buffer_in as *mut [S]).await?;
Ok(())
}
}
/// Helper encapsulating common I2S device operations.
struct Device<T>(&'static RegisterBlock, PhantomData<T>);
impl<T: Instance> Device<T> {
fn new() -> Self {
Self(T::regs(), PhantomData)
}
#[inline(always)]
pub fn enable(&self) {
trace!("ENABLED");
self.0.enable.write(|w| w.enable().enabled());
}
#[inline(always)]
pub fn disable(&self) {
trace!("DISABLED");
self.0.enable.write(|w| w.enable().disabled());
}
#[inline(always)]
fn enable_tx(&self) {
trace!("TX ENABLED");
self.0.config.txen.write(|w| w.txen().enabled());
}
#[inline(always)]
fn disable_tx(&self) {
trace!("TX DISABLED");
self.0.config.txen.write(|w| w.txen().disabled());
}
#[inline(always)]
fn enable_rx(&self) {
trace!("RX ENABLED");
self.0.config.rxen.write(|w| w.rxen().enabled());
}
#[inline(always)]
fn disable_rx(&self) {
trace!("RX DISABLED");
self.0.config.rxen.write(|w| w.rxen().disabled());
}
#[inline(always)]
fn start(&self) {
trace!("START");
self.0.tasks_start.write(|w| unsafe { w.bits(1) });
}
#[inline(always)]
fn stop(&self) {
self.0.tasks_stop.write(|w| unsafe { w.bits(1) });
}
#[inline(always)]
fn is_stopped(&self) -> bool {
self.0.events_stopped.read().bits() != 0
}
#[inline(always)]
fn reset_stopped_event(&self) {
trace!("STOPPED EVENT: Reset");
self.0.events_stopped.reset();
}
#[inline(always)]
fn disable_stopped_interrupt(&self) {
trace!("STOPPED INTERRUPT: Disabled");
self.0.intenclr.write(|w| w.stopped().clear());
}
#[inline(always)]
fn enable_stopped_interrupt(&self) {
trace!("STOPPED INTERRUPT: Enabled");
self.0.intenset.write(|w| w.stopped().set());
}
#[inline(always)]
fn reset_tx_ptr_event(&self) {
trace!("TX PTR EVENT: Reset");
self.0.events_txptrupd.reset();
}
#[inline(always)]
fn reset_rx_ptr_event(&self) {
trace!("RX PTR EVENT: Reset");
self.0.events_rxptrupd.reset();
}
#[inline(always)]
fn disable_tx_ptr_interrupt(&self) {
trace!("TX PTR INTERRUPT: Disabled");
self.0.intenclr.write(|w| w.txptrupd().clear());
}
#[inline(always)]
fn disable_rx_ptr_interrupt(&self) {
trace!("RX PTR INTERRUPT: Disabled");
self.0.intenclr.write(|w| w.rxptrupd().clear());
}
#[inline(always)]
fn enable_tx_ptr_interrupt(&self) {
trace!("TX PTR INTERRUPT: Enabled");
self.0.intenset.write(|w| w.txptrupd().set());
}
#[inline(always)]
fn enable_rx_ptr_interrupt(&self) {
trace!("RX PTR INTERRUPT: Enabled");
self.0.intenclr.write(|w| w.rxptrupd().clear());
}
#[inline(always)]
fn is_tx_ptr_updated(&self) -> bool {
self.0.events_txptrupd.read().bits() != 0
}
#[inline(always)]
fn is_rx_ptr_updated(&self) -> bool {
self.0.events_rxptrupd.read().bits() != 0
}
#[inline]
fn update_tx<S>(&self, buffer_ptr: *const [S]) -> Result<(), Error> {
let (ptr, maxcnt) = Self::validated_dma_parts(buffer_ptr)?;
self.0.rxtxd.maxcnt.write(|w| unsafe { w.bits(maxcnt) });
self.0.txd.ptr.write(|w| unsafe { w.ptr().bits(ptr) });
Ok(())
}
#[inline]
fn update_rx<S>(&self, buffer_ptr: *const [S]) -> Result<(), Error> {
let (ptr, maxcnt) = Self::validated_dma_parts(buffer_ptr)?;
self.0.rxtxd.maxcnt.write(|w| unsafe { w.bits(maxcnt) });
self.0.rxd.ptr.write(|w| unsafe { w.ptr().bits(ptr) });
Ok(())
}
fn validated_dma_parts<S>(buffer_ptr: *const [S]) -> Result<(u32, u32), Error> {
let (ptr, len) = slice_ptr_parts(buffer_ptr);
let ptr = ptr as u32;
let bytes_len = len * size_of::<S>();
let maxcnt = (bytes_len / size_of::<u32>()) as u32;
trace!("PTR={}, MAXCNT={}", ptr, maxcnt);
if ptr % 4 != 0 {
Err(Error::BufferMisaligned)
} else if bytes_len % 4 != 0 {
Err(Error::BufferLengthMisaligned)
} else if maxcnt as usize > EASY_DMA_SIZE {
Err(Error::BufferTooLong)
} else {
Ok((ptr, maxcnt))
}
}
}
/// Sample details
pub trait Sample: Sized + Copy + Default {
const WIDTH: usize;
const SCALE: Self;
}
impl Sample for i8 {
const WIDTH: usize = 8;
const SCALE: Self = 1 << (Self::WIDTH - 1);
}
impl Sample for i16 {
const WIDTH: usize = 16;
const SCALE: Self = 1 << (Self::WIDTH - 1);
}
impl Sample for i32 {
const WIDTH: usize = 24;
const SCALE: Self = 1 << (Self::WIDTH - 1);
}
/// A 4-bytes aligned [Buffer].
#[repr(align(4))]
pub struct AlignedBuffer<T: Sample, const N: usize>([T; N]);
impl<T: Sample, const N: usize> AlignedBuffer<T, N> {
pub fn new(array: [T; N]) -> Self {
Self(array)
}
}
impl<T: Sample, const N: usize> Default for AlignedBuffer<T, N> {
fn default() -> Self {
Self([T::default(); N])
}
}
impl<T: Sample, const N: usize> Deref for AlignedBuffer<T, N> {
type Target = [T];
fn deref(&self) -> &Self::Target {
self.0.as_slice()
}
}
impl<T: Sample, const N: usize> DerefMut for AlignedBuffer<T, N> {
fn deref_mut(&mut self) -> &mut Self::Target {
self.0.as_mut_slice()
}
}